Bethesda are a highly overrated company. I enjoyed Skyrim and put many hours into it. But it was also a very overrated game. I really was not that into nor compelled by the game's main story or characters, and found myself not wanting to side with either side in the civil war, etc. I eventually did just to get that part of the story over with. But for the most part I just enjoyed exploring and messing around in the game world. And it was very anti-climatic that things like becoming Arch-Mage, for example, don't actually seem to hold more weight in the game world, as in no one gives two fucks, outside of the people at the Mage College. I think that kind of accurately described most of the story elements in the game, at least for me: very interesting set-up, but often an anti-climatic let-down after it was all over, and that includes how easy actually beating the great big world eating dragon was at the end.
The gameplay is fun, and I enjoyed it much more than I did trying to go back and play Oblivion, etc. But the game is also SUPER buggy, many of which they never bothered to patch or fix. And in general, I feel like even though they're very good at giving you good set-up, an interesting game world to play around in, etc., they're not terribly great at leaving you with that ultimate sense of fulfillment after you accomplish things, or certainly when you "beat the game". The DLC expansions were neat, and added some interesting things, but I ultimately felt like they should have focused a bit more on giving the player a few more in-world, in-story options, such as being able to actively decide not to side with either the Nords or the Imperials, and basically just say "fuck it" and become High King yourself. That would have been more satisfying. That is another thing, at least to me, was that after I had completed a vast majority of the main story, the civil war story, gone through just about all the of dungeons and done most of the missions, etc., I felt very little desire to start a new character and play through again. The idea of starting a whole new character was very appealing. But the idea of going back through most of that same story and same dungeons again, was not.
If they ever come out with Elder Scrolls VI, IF it's at least as good as Skyrim, I'd most likely want to play it. But I would hope that they would at least get better at polishing out the game bugs, and hopefully spend a bit more time giving the player even MORE options as far as story choices and ability to do things goes. The game world they made in Skyrim is great, it just needs to feel like certain things you as a character do actually matter more. And if they're going to focus so much on it being a big wide open sandbox experience....I suppose my suggestion would be, I'd like to see them just push that part of the exprience way more. Just go full bore and make it even MORE of a "just do whatever the hell you want" type of game. The game story should matter, and be interesting, of course. I'm just saying they should give the play even MORE of a robust array of options and choices as to how they actually want to have all that play out.
I've never personally played any of the Fallout series, but almost every fan I've talked to has always said that they liked the original two games, and that New Vegas (made by the original developers, not Bethesda), was a much better game than three.